public void MakeNullMove()
{
NullMoves++;
if (ColorToMove == Color.White)
{
MovesCount++;
}
_enPassants.Push(EnPassant);
_hashes.Push(Hash);
if (EnPassant != 0)
{
var enPassantRank = BitOperations.BitScan(EnPassant) % 8;
Hash = ZobristHashing.ToggleEnPassant(Hash, enPassantRank);
EnPassant = 0;
}
ColorToMove = ColorOperations.Invert(ColorToMove);
Hash = ZobristHashing.ChangeSide(Hash);
}
public void MakeMove(Move move)
{
var pieceType = PieceTable[move.From];
var enemyColor = ColorOperations.Invert(ColorToMove);
if (ColorToMove == Color.White)
{
MovesCount++;
}
_castlings.Push(Castling);
_hashes.Push(Hash);
_pawnHashes.Push(PawnHash);
_enPassants.Push(EnPassant);
_irreversibleMovesCounts.Push(IrreversibleMovesCount);
if (pieceType == Piece.Pawn || move.IsCapture() || move.IsCastling())
{
IrreversibleMovesCount = 0;
}
else
{
IrreversibleMovesCount++;
}
if (EnPassant != 0)
{
var enPassantRank = BitOperations.BitScan(EnPassant) % 8;
Hash = ZobristHashing.ToggleEnPassant(Hash, enPassantRank);
EnPassant = 0;
}
if (move.IsSinglePush())
{
MovePiece(ColorToMove, pieceType, move.From, move.To);
Hash = ZobristHashing.MovePiece(Hash, ColorToMove, pieceType, move.From, move.To);
if (pieceType == Piece.Pawn)
{
PawnHash = ZobristHashing.MovePiece(PawnHash, ColorToMove, pieceType, move.From, move.To);
}
}
else if (move.IsDoublePush())
{
MovePiece(ColorToMove, pieceType, move.From, move.To);
Hash = ZobristHashing.MovePiece(Hash, ColorToMove, pieceType, move.From, move.To);
PawnHash = ZobristHashing.MovePiece(PawnHash, ColorToMove, pieceType, move.From, move.To);
var enPassantField = ColorToMove == Color.White ? 1ul << move.To - 8 : 1ul << move.To + 8;
var enPassantFieldIndex = BitOperations.BitScan(enPassantField);
EnPassant |= enPassantField;
Hash = ZobristHashing.ToggleEnPassant(Hash, enPassantFieldIndex % 8);
}
else if (move.IsEnPassant())
{
var enemyPieceField = ColorToMove == Color.White ? (byte)(move.To - 8) : (byte)(move.To + 8);
var killedPiece = PieceTable[enemyPieceField];
RemovePiece(enemyColor, killedPiece, enemyPieceField);
Hash = ZobristHashing.AddOrRemovePiece(Hash, enemyColor, killedPiece, enemyPieceField);
PawnHash = ZobristHashing.AddOrRemovePiece(PawnHash, enemyColor, killedPiece, enemyPieceField);
MovePiece(ColorToMove, pieceType, move.From, move.To);
Hash = ZobristHashing.MovePiece(Hash, ColorToMove, pieceType, move.From, move.To);
PawnHash = ZobristHashing.MovePiece(PawnHash, ColorToMove, pieceType, move.From, move.To);
_killedPieces.Push(killedPiece);
}
else if (move.IsCapture())
{
var killedPiece = PieceTable[move.To];
RemovePiece(enemyColor, killedPiece, move.To);
Hash = ZobristHashing.AddOrRemovePiece(Hash, enemyColor, killedPiece, move.To);
if (killedPiece == Piece.Pawn)
{
PawnHash = ZobristHashing.AddOrRemovePiece(PawnHash, enemyColor, killedPiece, move.To);
}
else if (killedPiece == Piece.Rook)
{
switch (move.To)
{
case 0:
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.WhiteShort);
Castling &= ~Castling.WhiteShort;
break;
}
case 7:
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.WhiteLong);
Castling &= ~Castling.WhiteLong;
break;
}
case 56:
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.BlackShort);
Castling &= ~Castling.BlackShort;
break;
}
case 63:
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.BlackLong);
Castling &= ~Castling.BlackLong;
break;
}
}
}
if (move.IsPromotion())
{
var promotionPiece = GetPromotionPiece(move.Flags);
RemovePiece(ColorToMove, pieceType, move.From);
Hash = ZobristHashing.AddOrRemovePiece(Hash, ColorToMove, pieceType, move.From);
PawnHash = ZobristHashing.AddOrRemovePiece(PawnHash, ColorToMove, pieceType, move.From);
AddPiece(ColorToMove, promotionPiece, move.To);
Hash = ZobristHashing.AddOrRemovePiece(Hash, ColorToMove, promotionPiece, move.To);
_promotedPieces.Push(promotionPiece);
}
else
{
MovePiece(ColorToMove, pieceType, move.From, move.To);
Hash = ZobristHashing.MovePiece(Hash, ColorToMove, pieceType, move.From, move.To);
if (pieceType == Piece.Pawn)
{
PawnHash = ZobristHashing.MovePiece(PawnHash, ColorToMove, pieceType, move.From, move.To);
}
}
_killedPieces.Push(killedPiece);
}
else if (move.IsCastling())
{
// Short castling
if (move.IsKingCastling())
{
if (ColorToMove == Color.White)
{
MovePiece(Color.White, Piece.King, 3, 1);
MovePiece(Color.White, Piece.Rook, 0, 2);
Hash = ZobristHashing.MovePiece(Hash, Color.White, Piece.King, 3, 1);
Hash = ZobristHashing.MovePiece(Hash, Color.White, Piece.Rook, 0, 2);
}
else
{
MovePiece(Color.Black, Piece.King, 59, 57);
MovePiece(Color.Black, Piece.Rook, 56, 58);
Hash = ZobristHashing.MovePiece(Hash, Color.Black, Piece.King, 59, 57);
Hash = ZobristHashing.MovePiece(Hash, Color.Black, Piece.Rook, 56, 58);
}
}
// Long castling
else
{
if (ColorToMove == Color.White)
{
MovePiece(Color.White, Piece.King, 3, 5);
MovePiece(Color.White, Piece.Rook, 7, 4);
Hash = ZobristHashing.MovePiece(Hash, Color.White, Piece.King, 3, 5);
Hash = ZobristHashing.MovePiece(Hash, Color.White, Piece.Rook, 7, 4);
}
else
{
MovePiece(Color.Black, Piece.King, 59, 61);
MovePiece(Color.Black, Piece.Rook, 63, 60);
Hash = ZobristHashing.MovePiece(Hash, Color.Black, Piece.King, 59, 61);
Hash = ZobristHashing.MovePiece(Hash, Color.Black, Piece.Rook, 63, 60);
}
}
if (ColorToMove == Color.White)
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.WhiteShort);
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.WhiteLong);
Castling &= ~Castling.WhiteCastling;
}
else
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.BlackShort);
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.BlackLong);
Castling &= ~Castling.BlackCastling;
}
CastlingDone[ColorToMove] = true;
}
else if (move.IsPromotion())
{
var promotionPiece = GetPromotionPiece(move.Flags);
RemovePiece(ColorToMove, pieceType, move.From);
Hash = ZobristHashing.AddOrRemovePiece(Hash, ColorToMove, pieceType, move.From);
PawnHash = ZobristHashing.AddOrRemovePiece(PawnHash, ColorToMove, pieceType, move.From);
AddPiece(ColorToMove, promotionPiece, move.To);
Hash = ZobristHashing.AddOrRemovePiece(Hash, ColorToMove, promotionPiece, move.To);
_promotedPieces.Push(promotionPiece);
}
if (pieceType == Piece.King && !move.IsCastling())
{
if (ColorToMove == Color.White)
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.WhiteShort);
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.WhiteLong);
Castling &= ~Castling.WhiteCastling;
}
else
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.BlackShort);
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.BlackLong);
Castling &= ~Castling.BlackCastling;
}
}
else if (pieceType == Piece.Rook && Castling != 0)
{
if (move.From == 0)
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.WhiteShort);
Castling &= ~Castling.WhiteShort;
}
else if (move.From == 7)
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.WhiteLong);
Castling &= ~Castling.WhiteLong;
}
else if (move.From == 56)
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.BlackShort);
Castling &= ~Castling.BlackShort;
}
else if (move.From == 63)
{
Hash = ZobristHashing.RemoveCastlingFlag(Hash, Castling, Castling.BlackLong);
Castling &= ~Castling.BlackLong;
}
}
ColorToMove = enemyColor;
Hash = ZobristHashing.ChangeSide(Hash);
}